Method and means for stopping a weaving machine



March 14, 1961 E. PFARRWALLER 2,974,688

METHOD AND MEANS FOR STOPPING A WEAVING MACHINE Filed Sept. 14, 1955 3 Sheets-Sheet 2 18c F19. 7 18d 18b 18a X K 53 FY9110 15 20 18c (5T '54 18d 18b 18a IN VEN TOR.

[PW/N PFARRWALLER A T TORNEK March 14, 1961 PFARRWALLER 2,974,688

METHOD AND MEANS FOR STOPPING A WEAVING MACHINE Filed Sept. 14, 1955 3 Sheets-Sheet 3 My 104 $90 12 102 10a :81

IN VEN TOR.

ERWl/V PFZIRRWALLER A TTORNEY.

shed are moved trio pended claims.

States Pam Q METHOD AND MEANS FOR STOPPING A WEAVING MACHINE The/present invention relates to a method aiid means for stopping aweaving machine for correcting irregula'rities of the warp. a

The method according to the invention includes the ste p 'ot producing a control pulse for stopping the weavmg machine independence on an irregularity" of the warp-and 'on a predetermined angle of rotation of the 7 main shaft of-{theweaving machine, at which angle of rotation the' moveinent of the warp'threadschanging the shed'isstopped between the two extreme open shed-posh tions. 1 threads which do not change shedjiare nigved from'an extreme 'upper: or lower position toward closed shed positionhndback therefrom to the extreme position while the warp threadswhich do change shed are gmveaallthe way 'from extreme upper to extr'eme lower 'pbsitio r vice versa; Inthe methojdaccording' to the inventioiif the movement "of {the warp threads which do not ehangeshed is stopped somewhere'b'e'tween oneof their extreme positions and'the positions where they'are normally reversed or is'stopped at the point of reversal. fl Depen'ding onfthe speed 'ots theloom and the masses which'rnust be stopped; the stoprmotion actuated prior t the "are means" for perforniingithe aforesaid aim-red in;-

clud'efa"control devicef which efiects stopp g dr me 40 p returns the idle shuttle 25 below the shed from the receiving'mechanism to the picking' mechamsm.

weaving rnfacliinein dependencefbn ari'irregularity offline I warp as wares on a;predeteifmined rotational angular position ofthemai'n of the weaving'niachine. -'=T'he" 'me'ansffor performinghhe methiid also include a device a"inanner 'that at the' predetermined angular; position:

of the main i shaft'i the: i movement" of the :warp threads changingthe? shed iststopped between the two extr'ejmechangewshed .The arp threads ,which ado aetiieaaa an: thne sgwhi h do. ha ge s ed more llg -h waiv from one. egttreme positionltolthe'lptlier extreme' of the invention drivenwb'y. the" main pshaft :15 -throughreducing gear train 43 'Ihelr otational speed of the shafts 41;..and 42 is. one-fourth of that ofthe main shaft 15 ,Sets o'f cams III V roment' when actual stoppage of the Hloomis desired. 1 1 r t islsi ti mal wer P w tion toward closed shed position and backfwhile ft-he Shown 76 I 2,974,688 Patented Mar. 14, 1961 Fig. 4 is a diagrammatic illustration. of the stopping device according to the invention;

Figs. 5 and 9 are diagrams showing the movements of the lay and of the heddles;

Figs. 6, 7,- 8, and 10 illustrate different positions of the warp threads when the weaving machine is stopped; Figs. 11 and 12 are large scale illustrations of the.

I belt pulley 14- by means of a belt 13. A disc clutch mounted in the pulley 14 and not shown drives the main shaft 15 of the loom. The shaft 15 primarily drives the parts of the loom which must be moved continuously or intermittently during normal operation of the loom. Theshaft 15 'actuates the warp beam 16 and the warp 17 which moves through the heddles supported by one or a plurality of frames 18, the latter being actuated by thef shaft 15 for opening, closing-and changing of the shed. The shaft 15 also actuatesthe Warpactuating i b'eam19 and the cloth beam 20 for winding theclothll.

weft thread is pulled from a $1 27 Supported by a carrier 26-outside of the shuttle 2,5 and is picked by the shuttle 2.5 through theshed towards the receiving mechamm 23, whereupon the weft thread 24 beaten up by means of a lay actuated by the shaft 15;

.'Ihe sh uttle 25 after the weft thread 24 has been dis; engaged therefrom, is moved onto a return mechanism by suitable means in the shuttle receiving mechanism 23. 'I*h'e"return mechanism, driven by the main shaft 15,

A drive 32 forthe actuating beam "19 is mounted on A a" lea ue shield, 12:: which is connectedwiththeright which 'Iactuates the Lheddles controlling the. warp .in' 'such isinfa. housing 37 and acts on the main shaft -15, is

applied at improper operating conditions after disengagement of the clutch in the'heltpulley 14- for immediately stopping themain shaft 15 and all parts driven thereby.

Thebnake in the housing 37 is disengaged in known manner by means-of the control levers 33.wit hout engaging the clutch in the pulley 14. 'Iherenpon the disconnected m'aihsha-ft 15 canbe turn'edby means of a hand wheel' 38, tor example for adjusting individual loom parts, to -assume a desired position relative tozero posi- I tionof the m'ain shaft. {The latter-is thereby revolved 3 until? it assumes the angular position corresponding to the. I 'flo'om partwhichis-being checked.

7 Figs. 2"'and-3 illustrate a device for actuatingheddles 18a toelfidr There rare twogshafts 4-1 and-.42 whichare 4522 to 45drandflod to d a'rexmadegtaston thetshafts various localities around the loor'n. The brake; which I ee 41 10.4. .4. e

41;.ana4zj,;r sp fiv1y rt sharew e-e tr nces t its ta I aartess 3 18a to 18d through elbow levers 48a to 48d, respectively. A dial 50, showing angles to 360 on a scale 51, is mounted on the main shaft. A pointer 52 mounted on a casing 40 indicates the angular position of the shaft on the scale 51. The position of the heddles shown in Fig. 2 corresponds to an angular position of 30 of the shaft 15. Fig. 3 shows the extreme upper position 53 and the extreme lower position 54 of the upper beams of the heddle frames.

Fig. 4 illustrates a device for stopping the weaving ma chine, numeral 55 designating a brake disc on the main shaft 15 and located in the housing 37 (Fig. l). A lever 57 swingable on a pivot 58 and having a free end which is connected with a spring 59 serves to operate a brake band 56. The free end of the lever 57 is also connected by means of a link 61 with a lever 62 revolving about stationary fulcrum pin 63 and having a recess 64 receiving a locking lever 65 mounted to a stopping shaft 66 which is supported by the frame of the weaving machine.

The stopping device includes control means having a contact disc 67 supported by the main shaft 15; a contact element 68 cooperating with slide contacts 69 is movably mounted on the disc 67 and can be fixed in a selected position. The disc 67 is revolvable on a hub 70 which is fast on the shaft 15, the disc being pressed to a flange 72 of the hub 70 by means of a screw 71. The flange 72 is provided with a scale 73. The disc 67 is provided with a marker 74 for indicating the relative angular position of the disc 67 and the flange 72. The contact element 68 can be fixed in any desired position by tightening a screw 88 which extends into a nut placed on the back of the disc 67, the pointer 89 at one end of the element 68 showing the adjustment angle relative to the marker 74 on a scale 90. p

The warp 17 moves over rods 75 supported by the frame of the weaving machine and the individual warp threads move through individual feelers 76 arranged in a file one behind the other on a contact rail 77. A solenoid 80 is interposed in the electric circuit 78 which is supplied by a'battery 79 and includes the rail 77 and the slide contacts 69. An armature 81 is held in the upper position shown in Fig. 4 by means of a spring 82. The armature 81 is provided with a hook 83 which-cooperates with an arm 84 of the locking lever 65 on the stopping shaft 66. The arm 84 is pressed upwards by a spring 85.

If there is an irregularity in the warp, for example a broken warp thread, a pulse is produced by the irregularity as well as at a predetermined angular positionof the main shaft '15 which pulse energizes the solenoid 80. If a warp thread breaks, the respective thread feeler 76 drops onto the -rail 77, grounding the circuit 78. The

circuit 78, however,- is not closed until also the slide con tacts 69 are connected. V

If the circuit 78 is closed, the armature 81 is pulled down against the actionof the spring 82 and the hook.

clockwise by theaction of the-spring 59. The latter also moves the brake lever 57 clockwise, tightening the brake band 56 on the brake 'disc .55. This initiates brakingof movement of the frames 18a and 18b commences at the points i, whereas the frames 18c and 18d begin their movement at point k. The last-mentioned heddle frames remain in the upper shed position in which they already were and assume only temporarily a position below the extreme upper shed position.

The angular position VI of the main shaft 15 in the diagram Fig. 5 corresponds to the position of the heddles 18a to 18d in Fig. 6 which are still in their extreme upper shed positions (18b, 18c, 18d) and in the extreme lower position (1811). The warp 17 and the fabric 21 extend between the warp beam 16 and the cloth beam 20. The lay 28 with the reed 29 is still in rest position.

For correcting an irregularity in the warp, the weaving machine must be stopped While the angular position of the main shaft is between m and n, i.e. in the range which is shaded in Fig. 5. The position of the heddle frames in the angular position VII (Fig. 5) of the main shaft corresponds to the situation shown in Fig. 7. The warp threads extending through the heddles 18a and 18b have already been crossed at position 0 in Fig. 5, the heddles being within the range defined bytheir extreme positions 53 and 54 at the moment they are stopped, so that drawing in of new warp threads to replace the broken threads is facilitated. The eyes of the heddles are considerably better accessible for threading when the heddles are in an intermediate position than when they are in their extreme upper or lower position. Accessibility of the eyes of the heddles which are in uppermost position is frequently impaired by the upper beams of the heddle frames which are in their lower shed position.

The angular range between the positions m and n of the main shaft is ahead of the angular position g of the main shaft 15 in which position the reed 29 is beating up a weft thread, the distance p between the angular positions It and g being preferably made so great that there is suflicient time to accelerate the weaving machine warp. The angular positionVlII corresponds to the situationvv shown in Fig. 8 where the heddles are in substantially the same position as in Fig. 7. The lay 28 l and the reed 29, however, are moving to the left toward rest or inactive position. The first angular position q of this range is at a distance s from the beat-up position g, so that, when the weaving machine is restarted, the beginning of the movement of the lay cannot cause irregularities in the fabric. To accomplish this, it is sufficient that the reed 29 is just a little removed from the last inserted Weft thread. The distance s can therefore be considerably smaller than the distance p.

The angular positions V11, and VILI in 'which the weavingmachine is standing still are not the positions in which an impulse for stopping the machine is produced.

' The dependency of the production of the impulse for the main shaft 15, stopping the main shaft 15 after ,ro-' 1 tation through a certain braking angle.

There are, of course, conventional mearis.(not shown),

for interrupting current supply tothe 'motor '11 and/ or for disengaging the clutch in the pulley 14. 1 1

The line A in the diagram Fig. 5 indicates the movement of the lay; From point' f the lay r'noves toward the fabric beatingup theinserted weft thread at po'int g and returning a'tpoint I tojits idleposition The curve- B indicates the movem entfof the heddle frame18a, the 1 curve .C indicates the movement of the heddle ffame 18b, and the themovement'ofthe lied-j dleframesl-SC and 18d whichare shown-in Figf-3; "The stopping .the machine on the irregularity in the warp is effected by the contact made between the respective warp thread feeler and the rail 77. f

The dependency of the stopping of the weaving machine on a predetermined angular position of the main shaft '15 is effected as followsz The mark 74 on the V contact disc 67 is placed at the desired angleon the scale 73 (Fig. 4). The setting shown in the drawing corresponds to an angular position of the shaft 15 amounting to 30 past thevzero position of the shaft 15. In order to be sure that the machine'is actually at astandstill at this angular position of'its main shaft, the pulse must be produced so many angular degrees ahead;

of the desired angular degree as correspond to the braking angle. 1

In machines operating at a very slow speed a braking and the moment when the machine comes to a standstill is between 20 and 30. Therefore, the pointer 89 must be moved through this angle in the direction of rotation of the disc 67T(arrow 86), .as is shownin Fig. 4.

The impulse for the position q to r must be produced before a weftthi'ead is'be'at'enup at positiong. This has the advantage thafthefbr-aking angle is reduced because the en'ergyrequiredtor beating up the inserted weft thread retards the shaft 15 in addition to the eifect of the brake 55,56, so that the machine will be stopped sooner. r l i 'In cont-radistinction to the operation shown in 'Fig. 5, the heddles are simultaneously moved in the operation illustrated in the motion diagram F-ig. 9. The heddle frames 1 8a and 1803 which retain the existing shed position for the subsequent pick, move from the extreme positions 54, 53 into a half shed position as indicated by the lines B and E in which the warp actuated by the heddles 18a and 18d is approximately in the middle between lower shed position, respectively between upper shed position and middle shed position. The heddles 18b and 18:: change the shed according to the curves C and D.

Fig. 10 shows the position of the heddles when the machine stands still at the angular position X ('Fig. 9) of the main shaft in which position the warp threads changing the shed cross each other. The mechanism may be adjusted for other angular positions which are between the lines m and n in Fig. 9, the end'of the range between these lines, i.e. the line n, being at a distance p from the beat-up position 3 for the reasons explained supra.

The radii I to IV marked on the cams 45a and 46a in Figs. Ill and 12, respectively, indicate the points of the cams in which the cam follower rollers of the levers 47 (Fig. 2) contact the cams in the intermediate positions Z and Z in which the weaving machine is brought to a standstill in dependence on the angular position VI in Fig. 5. The rad-ii I to 1V assume different positions de pending on the choice of the angular position for stopping the machine within the ranges shown by the shaded areas in Figs. 5 and 9.' The cams 45a and 461: shown in Figs. 11 and 12 are designed for a binding 1:3, the cams making a quarter turn at each pick. At the transition from lower shed to upper shed in the intermediate position according to the radius 11, the heddles'are ina lower intermediate position than at the positions according to the radii (I, HI, and 1V, the radii HI and IV corresponding to the half shed positions of the heddles remaining in their sheds. At the angular position, in which the movement of shed changing warp threads is stopped in a position situated between the two extreme positions at open shed, either all thread changing warp threads may be in this intermediate position or a part of the warp threads may, for any reason, remain in their extreme position.

number or an even division thereof, so that the cam.

contacts a cam follower roller always at the same angular position of the main shaft 15. The cam 91 cooperates with a lever 92 which swings on a stationary pin 93. The

I scale 107. This mark indicates an angle [3 of 45.

upper end of the lever 92 is pulled to the left by a spring 94 for pressing the .cam follower roller 95 rotatably mounted on the lever 92 against the cam 91. An ad justable abutment screw '96 is screwedinto the free end of the lever 92 which screw can be secured in the desired position by manipulation of a lock nut 97.

A warp thread feeler 76 is provided for each warp thread '17 which is guided by rods 75, the thread feelers being arranged in a series one behind the other on a contact rail 77. An electric circuit 78' connects a battery 79 with a solenoid 80' whose armature 81' is pressed upwards by means of a spring A latch 99 pivoted toa bolt 101 is connected with the armature 81' by means of a link 98. A The right end of the bolt or tappet L101 carries a head 102 abutting against a lever or arm 103 which is fast on a stopping shaft 66 and which is pressed to the. left by a spring 104 so that a collar 102' ofthe head 102 abuts against the side shield 12 of the frame Qfwth weave ing machine. 1

In' the position shown in Fig. 13 the solenoid 80' is not energizedand the pawl 99 is lifted due to the action of" the spring 82 so that the latch is out of the way of the abutment 96.

At an irregularity of the warp, for example if a warp thread is broken, the respective warp thread feeler 76 drops onto the contact rail 77 so that the circuit 78 is closed and the solenoid 80' is energized and the armature 81' is pulled down. Thereby the latch '99 is pulled down to the position indicated by dash-dot lines in Fig. 13. As long as the roller follows the circular portion of the surface of the cam 91, the abutment 96 is in the position shown in solid lines and does not touch the latch 99. However, when the cam portion 108 runs onto the roller 95, lever 92 is pressed into the position shown in dash-dot lines and the abutment 96 moves the latch 99 and the bolt 101 to the right so that tion of the spring 104. The shaft 66 carries a pawl 65 corresponding to the right arm of the lever 65, 84 of the device shown in Fig. 4, the pawl being taken out of the recess 64 of the lever 62 affording engagement of the brake 55, 56. The last described mechanism is the same as the one shown in Fig. 4 and its showing has not been repeated in Fig. 13.

The cam 91' is revolvable on a bushing which is fast on the shaft 15 and which has a flange 106. The relative position of the cam 91 and of the flange 106 can be fixed by tightening a screw screwed into the cam 91 and having a head engaging the flange 106. The latter is provided with a scale 107 indicating the angular positions 0 to 360 of the shaft 15.

A mark 109 is provided on the cam 91 opposite the The angle [3 is composed of an angle of 60, which is the angular position of the shaft 15 at which the weaving machine is to be stopped, minus a brake angle of '15. The shaft 66 is revolved at an angular position of 45 of the main shaft 15 for initiating'the braking operation. The shaft 15 does not come to a standstill until it has revolved through another 15.

Instead of providing an adjustable abutment 96 on the cam follower lever 92, the latch or pawl 99 may be made longitudinally displaceable, for example by making variable the length of the bolt 101. As another modification, an adjustment screw may be provided at the left end of the latch 99 instead of providing the adjustable abutment 96 on the lever 92. The latch 99 may be pivoted to the lever 103, omitting the bolt 101.

What is claimed is:

In a weaving machine for producing a fabric whose pattern is different from the pattern characteriied by 1:1 whereby certain warp threads change shed while other warp threads do not change shed: a main drive shaft, a shedding mechanism operatively connected to said main drive shaft and including control means effecting movement of the warp threads which do not change shed to a position between their extreme end positions at open shed and closed shed position and back to the previous extreme position during periods of time when the Warp threads which do change shed move from one to the other of their extreme end positions at open shed, a lay operatively connected to said main drive shaft and being between a. retracted position and beat-up position during said periods of time, and an apparatus for stopping the weaving machine including first means responsive to and actuated by an irregularity in the warp, second means responsive to and actuated at a predetermined angular position of said main drive shaft during said periods of time, and means for stopping the weaving machine upon coaction of said first and said second means, said second means including a cam rotating synchronously with the main shaft of the Weaving machine, said stopping means including a lever provided with a cam follower roller engagedby said. cam, a stopping shaft, an arm on said stopping shaft, a displaceable tappet abutting against said arm, a pawl pivoted to said tappet, and pawl actuating means for moving said pawl into a position in which it can be abuttedby said lever, said pawl actuating means being operatively connected to said first means for moving said pawl into the position in which it can be abutted by said lever for displacing said tappet by said lever when the main shaft of the weaving machine is in the predetermined angular position and after occurrence of an irregularity in the warp.

References Cited in the file of this patent UNITED STATES PATENTS 2,506,645 Kellogg et a1. May 9, 1950 2,600,667 Mason June 17, 1952 2,639,732 Moessinger May 26, 1953 2,647,545 Budzna et a1. Aug. 4, 1953 2,654,397 Darash Oct. 6, 1953 2,679,266 Dill May 25, 1954 2,727,538 Widmer Dec. 20, 1955 

